The B-King, like the Hayabusa, has two fuel injectors per cylinder. The secondary injectors don't work as often as the primary ones do. They start to come in around 4500 rpm or so, depending on how much throttle you're giving it. The moral of the story being the secondary injectors get plugged up a lot easier than the primary ones do,. Perhaps the person you bought the bike from rode it rather sedately, and never used the secondary injectors. And thus they are plugged up bad. It requires tearing the bike apart big time to get to them. It would likely be best to have your local Suzuki shop do it.
The coils on these bikes sit tight on the spark plugs. Point being, you have to disassemble the bike to the same degree to get to them as you do the injectors. I highly doubt the coils are bad. I suspect plugged secondary injectors.
BTW, the secondary injectors are responsible for a huge amount of the fuel injected at high rpms and throttle settings. For instance, at 8000 rpms, and 80% throttle, the secondary injectors are providing around 90% of the burned fuel. Thus you can see what would happen if they are plugged up.
Last edited by cbxer55 on Wed 18 Aug 2021 - 16:29; edited 1 time in total